The present invention relates to a process for fireproofing porous synthetic sheet material, particularly material comprising a porous polyurethane matrix, embedded with polyester, polyamide and/or polyethylene fibers, and a cover film of compact polyurethane resin. The present invention relates, in particular, to a process for fireproofing the many types of synthetic sheet material currently available on the market under various trade names and commonly known as "artificial leather", i.e. commonly used as artificial leather in place of real leather for upholstery, clothing, shoes and similar.
Most types of artificial leather normally used in industry and currently available on the market are generally known to be made using appropriate polymer resins, usually polyurethane, foam and/or porous resins (i.e. having microscopic pores visible only under an electronic microscope) which, unlike real leather, are all highly inflammable. The inflammable nature of the said known types of sheet material and the relatively harmful nature of the fumes produced when they are burned are two of the major reasons preventing their widespread employment, particularly in public premises such as theatres, cinemas, etc. Though various chemical additives exist which may be added to the said polymer resins of which the said artificial leather is formed, or which may be applied to the same at a later stage, such additives merely provide for retarding combustion of the said artificial leather and in no way provide for rendering it fireproof. Consequently, the danger underlying the said material, using known fireproofing processes, is simply reduced, not eliminated. Furthermore, the employment of fireproofing additives greatly impairs the appearance of the said artificial leather the scope of which is thus reduced.